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arXiv · 2404.04622

Geometric invariant theory for graded additive groups

Yikun Qiao
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Abstract

We consider geometric invariant theory for \emph{graded additive groups}, groups of the form $\mathbb{G}_a^r\rtimes_w\mathbb{G}_m$ such that the $\mathbb{G}_m$-action on $\mathbb{G}_a^r$ is a scalar multiplication with weight $w\in\mathbb{N}_+$. We provide an algorithm of equivariant birational modifications, such that we can apply the geometric invariant theory of B\'erczi-Doran-Hawes-Kirwan. In particular, the geometric $\mathbb{G}_a^r$-quotient exists. This complements B\'erczi-Doran-Hawes-Kirwan, in the special case of one grading weight.

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Yikun Qiao. 2024-04-06. Geometric invariant theory for graded additive groups. https://arxiv.org/abs/2404.04622

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